Enzyme compositions comprising pentosanases have been used to treat starch-containing compositions such as starch suspensions or solutions in starch production, brews, waste waters, doughs, and cereal products. Viscosity reduction of starch solutions, doughs, and cereal products, and purification of aqueous based starch-containing compositions are reported as resulting from the enzymatic treatment. Pentosanases have also been used to increase the softness of bread and other leavened products.
Regarding aqueous-based systems, Palmer et al, "Influence of Enzyme Distribution or Endosperm Breakdown (Modification) During Malting" ASBC Journal, vol. 43, no. 1, pp. 17-26 (1985) teaches that during the malting of barley, alpha-amylase, endo-beta-1,3:1,4-glucanase, pentosanase, and endo-beta-1,3-glucanases are developed. It is reported that steeping procedures and gibberellic acid can alter the pattern of enzyme development and the release and distribution of enzymes in the starchy endosperm.
Wieg, Von A. J., "Enzymatic Treatment of Waste Water From Wheat Starch Industry," Starch, vol. 36, no. 4, pp. 135-140 (1984) teaches the enzymatic treatment of waste-water from the wheat starch industry so as to reduce the biochemical oxygen demand of the waste water. The enzymes used to treat the waste water are alpha-amylase, cellulase, hemicellulase, beta-glucanase, and pentosanase.
Tegge et al, "Enzymic Hydrolysis of Various Starches" Starch/Staerke, vol. 38, no. 10, pp. 329-335 (1986) and its Chemical Abstract No. 224503r, vol. 105, p. 617 (1986) discloses the addition of pentosanase to commercial starches with amylolytic enzyme preparations. It is reported that the pentosanase did not affect viscosity and filtration of the hydrolyzates.
Drews, "Amylograms With Respect to Some Quality Criteria of Rye and its Mill Products," Brot. Gebaeck, vol. 23, no. 9, pp. 165-170 (1969) and its Chemical Abstract No. 65520a, vol. 72, page 261 (1970) discloses the addition of rye mucin to a wheat starch suspension. It is reported that the viscosity maximum depends on the soluble pentosans and that the removal of soluble material from rye flour considerably decreases its amylographic maximum.
Bruemmer, J., "Baking Components," Brot. Gebaeck, vol. 25, no. 11, pp. 217-220 (1971) and its Chemical Abstract No. 98049q, vol. 76, page 333 (1972) discloses the relative effects on the viscosity of rye flour suspensions exhibited by various enzymes such as protease, pentosanase, and alpha-amylase.
Fretzdorf, B., "Determination of Beta-xylosidase Activity in Rye, " Z. Lebenson Unters. Forsch, vol. 167, no. 6, pp. 414-418 (1978) and its Chemical Abstract No. 90:82674t, vol. 90, page 213 (1979) discloses the determination of beta-xylosidase in rye extracts and commercial enzymes such as cellulase and pentosanase.
Regarding doughs and baked goods, Weipert, D., "Rheology of Rye Dough," Getreide Mehl Brot., 26(10) pp. 275-280 (1972) and its Chemical Abstract No. 56693f vol. 78, page 388 (1972) discloses the treatment of rye dough for two hours at 30.degree. C. with two pentosanases (EL-5-72 and EL-15-72). The article reports the attainment of softer doughs and increased bread volume. The pentosanases and proteases are taught as lowering dough viscosity the most compared to results obtain with three amylases, cellulase, a pectinase, and a malt flour. The pentosanase EL-5-72 is indicated as being free of amylase and protease activity.
Weipert, D., "Rheology of Rye Doughs," Ber Getreidechem-Tag Detmold, pp. 189-203 (1972) and its Chemical Abstract 122859t, vol. 78, page 349 (1973) discloses lowering of rye dough viscosity with enzymes. It is taught that the use of pentosanase and amylase gives more maltose and bread volume than does protease and amylase.
Great Britain patent specification no. 1,332,903 to Casier (Oct. 10, 1973) discloses that water-soluble pentosans from wheat and rye grains can have certain beneficial effects as regards to certain aspects of panification, promoting swelling, retention of water, or favoring the structure itself of the finished wheat or rye bread product. The Great Britain patent publication teaches that water-insoluble pentosans have remarkable effects on panification, making it possible to produce a perfectly edible and pleasant-tasting bread from pure starch. It is further indicated that the use of water-insoluble pentosans in the production of bread from flours such as the various soft wheat flours, cassava flour, potato flour, maize flour, rice flour, and any starch-bearing cultivated vegetable would be particularly favorable. In the process of the Great Britain patent publication, the water-insoluble pentosans are extracted for use as an adjuvant for panification and/or a gelling agent by removing most of the water-soluble components from a gramineous plant starting material, treating the residue with a sufficiently strong base to extract the water-insoluble pentosans from the residue without solubilizing the starches thereof, and electrodialyzing the extract at a pH above 6 and subsequently drying the latter. The treatment of the residue with the strong base is conducted at a temperature not exceeding 55.degree. C. and at a pH of from 8 to 13.
Rotsch, A., "Possibilities for Utilization of New Enzymic Baking Additives," Brot Gebaeck, vol. 23, no. 10 pp. 202-203 (1969) and its Chemical Abstract No. 120153k, vol. 72, page 226 (1970) discloses the addition of microbial pentosanase to rye and wheat breads, waffles, and other bakery products. The addition of the pentosanase is reported to increase the volume and lightness and improve the crumb quality of rye and wheat breads. It is also taught that the pentosanase lowers the dough viscosity and facilitates the manufacture of waffles and other bakery products.
Canadian Patent No. 603,953 and corresponding U.S. Pat. No. 2,821,501 to Simpson disclose that in the extraction of starch from wheat which contains pentosan gum, the gum is degraded with a pentosanase enzyme but the starch itself is not degraded. To avoid attack on gluten by proteolytic enzymes, it is indicated as being preferred to remove the gluten from the flour before the enzyme is added to the starch slurry. The enzyme is prepared by aerobically growing an organism selected from the group consisting of Bacillus pumilus, Bacillus subtilis, Bacillus licheniformis, and Bacillus polymyxa. It is disclosed that the release of starch from the pentosans increases the recovery of starch from flour.
The use of pentosanases in bread doughs to influence loaf volume or crush is disclosed in: 1) Johansson et al, "Investigations on the Composition of Water Soluble Pentosans in Flour and Doughs of Wheat and The Effect of Pentosanases on the Machinability During Dough Development," Sver Utsaedesfoeren, Tidske, Vol. 8 (3-4) pp. 282-301 (1971) and its Chemical Abstract No. 117310r, vol. 75 page 140 (1971), and 2) German Offen. 2,227,368 to Krebs et al (Oct. 17, 1974) and its Chemical Abstract No. 71839j, vol. 82 page 347 (1975).
The Johansson et al article teaches that the use of an enzyme preparation known as Rhozyme HP-150 increases loaf volume without any appreciable deterioration of the crumb. It is further taught that kneading did not significantly affect the pentosan composition.
The German patent publication to Krebs et al discloses the addition to bread doughs of a composition comprising alpha-amylases, protease, pentosanase, and a swelling agent. The swelling agent may be corn starch, guar gum, carob bean flour, galactomannan, or pectin. It is reported that pentosanase favorably influences the crush.
Great Britain Patent Publication No. 2,150,933A and corresponding French Patent Publication No. 2,555,602 disclose that pentosans occur in cereal flour, in which they bind water, and they contribute to stiffening or staling of bread after baking. According to these patent publications, a reduction in the pentosan content of the flour reduces the liability to stiffening. The references teach the production of a pentosan-degrading enzyme and a composition containing it which has pentosanase activity, particularly at higher temperatures of around 90.degree. C. The enzyme compositions are prepared by fermentation of Talaromyces Emersonii, particularly strain IMI 116815. The enzyme is added in aqueous medium to treat wheat flour to reduce the stiffening or staling of the bread. The enzyme composition is also used to reduce the viscosity of starch solutions in the production of starch.
U.S. Pat. No. 3,512,992 discloses the use of a pentosanase composition for increasing the softness of bread. The pentosan-degrading enzyme preparation may be derived from Bacillus subtilis or Aspergillus niger. Commercial enzyme preparations which may be used in the process of U.S. Pat. 3,512,992 are Rhozyme HP-150 sold by Rohm and Haas Co., Cellulase 4000 sold by Miles Laboratories, and Cellulase-APIII sold by Amano Pharmaceutical Co. Ltd. The Rhozyme HP-150 also contains as minor constituents, amylase, protease, pectinase and anthocyanase.
According to U.S. Pat. No. 3,512,992, bread and other leavened products are prepared by intimately combining with flour and other dough-forming ingredients, water and an enzyme preparation having a pentosanase activity of between 2,000 and 24,000 pentosanase units per 100 pounds of flour, working the resulting mixture to form a developed dough and baking or frying the dough. The pentosanase activity (P.U.) is determined by the method of Simpson (Can. J. Microbiology, 131-139, 1954) using purified wheat pentosan as the substrate reacting at pH 5.0 at 30.degree. C. for 30 minutes. The process may be used to prepare cakes and doughnuts as well as in the preparation of bread.
According to the patent, the incorporation of the pentosan-degrading enzyme preparation results in a surprisingly lasting softening effect on baked bread. It can be used for preparing bread in a batch procedure or in a continuous procedure. In the continuous process, the ingredients are first mixed in a mixing zone, and the mixed products are then moved to a developing zone where the dough is subjected in a continuous manner to mechanical working so as to develop the gluten. After passing through the developing zone in a continuous manner, the dough is forced through an orifice into a series of baking pans which are moved into a proofer, where the dough is allowed to rise.
"Grain Processing Opportunities with Genencor's GC123," a manufacture's literature article by Genencor, Inc., 180 Kimball Way, South San Francisco, Calif. 94080 reports that a cellulase from the microorganism T. reesei, namely Genencor's enzyme preparation GC123, possesses powerful pentosan degrading activity. It is further reported that the enzyme preparation contains very high levels of cellulase and beta-glucanase activities. It is taught that GC123 improved certain filtrations and reduced viscosity and is also capable of degrading wheat and barley pentosans.
Suggested applications for the Genencor enzyme preparation which are mentioned in the Genencor literature include: 1 the elimination of "sticky beak syndrome" associated with barley feeding to poultry, 2) reduction of mash viscosity, improving the watering of spent grains, and reduction in the energy requirement for spent grain drying in the distilling industry, 3) facilitation of dough formulation with less water, reduction of "stickiness", and improved performance using Anza wheat in the production of noodles and pasta products, 4) elimination of the "gummy" texture of oat products, 5) allowance of the use of wheat, oats, and rye without the usual viscosity problems in the production of cereal products and snack foods, 6) reduction in the water content when formulating grains for flaking, puffing or extrusion, 7) retarding staling of bread, 8) relaxing dough for cracker production, and facilitation of the use of "sticky" cereals in new product formulations, 9) providing new opportunities for formulating pre-mixed products, cakes and biscuits, 10) increasing the yield of prime starch in wheat wet milling, 11) facilitation of bran removal when added to tempering water, 12) upgrading millers by-products such as shorts and fiber, and 13) reducing both steeping time and starch in fiber in corn wet milling.
However, none of the above references teach or suggest the enzymatic treatment of a farinaceous material with pentosanase or beta-glucans to produce a hydrolysis product which reduces the water regain or increases the tolerance to moisture of low moisture content comestibles such as cookies, crackers, cereals, flours, flour fractions, and plant protein extracts.